1) What mass of Na2CO3 is required to make 50cc of its seminormal solution?

Explanation:

Hello,

In this case, by considering the given seminormal solution, we infer it is a 0.5-N solution which means that we can obtain the equivalent grams as shown below for the 55 cc (0.055 L) volume:

Next, since sodium carbonate has two sodium ions with a +1 oxidation state each, we can obtain the moles:

Finally, the mass is computed by using its molar mass (106 g/mol)

Regards.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.

the answer is c. nacl